Related Clues:

• Persian Gulf cargo
• In need of refinement
• Lacking subtlety, say
• Potty-mouthed
• Like shock rocker
• Input for a refinery
• Hastily fashioned
• Oil variety
• Unsubtle
• Like raw oil
• Oil? Carful does, regularly
• Like the humor of some limericks
• Without tact
• Primitive; oil
• Charlie's discourteous and rough